3rd Quarter Cumulative Review ALL of the following problems WILL appear on your quarterly exam and again on your REGENTS exam. SO TAKE SOME NOTES Do not try to copy down each problem, just make a note of the topic and then find a similar problem on an old exam to study from Do not try to study your entire notebook. Use your review sheet, this presentation, and your old tests, midterms, and quarterlies to study

Significant Figures Which measurement has the greatest number of significant figures? 6.060 mg 60.6 mg 606 mg 60600 mg Correct Answer = A

Percent Error A student intended to make a salt solution with a concentration of 10.0 grams of solute per liter of solution. When the student’s solution was analyzed, it was found to contain 8.90 grams of solute per liter of solution. What was the percent error in the concentration of the solution?  1.10%  8.90%  11.0%  18.9% Correct Answer = C

How to find (Average) Atomic Mass If 75.0% of the isotopes of an element have a mass of 35.0 amu and 25.0% of the isotopes have a mass of 37.0 amu, what is the atomic mass of the element? 35.0 amu 35.5 amu 36.0 amu 37.0 amu Correct Answer = B

Atomic # and Mass # What is the symbol for an atom containing 20 protons and 22 neutrons? Correct Answer = Choice #1 Ca-42

Isotopes Neutral atoms of 35Cl and 37Cl differ with respect to their number of electrons protons neutrons positrons Correct Answer = C

Rutherford’s Gold Foil Experiment In an experiment, alpha particles were used to bombard gold foil. As a result of this experiment, the conclusion was made that the nucleus of an atom is smaller than the atom and positively charged smaller than the atom and negatively charged larger than the atom and positively charged larger than the atom and negatively charged Correct Answer = A

Compounds vs. Elements Which substance can be decomposed by a chemical change? Co CO Cr Cu Correct Answer = B

Periodic Table Forming Ions When metals form ions, they tend to do so by losing electrons and forming positive ions losing electrons and forming negative ions gaining electrons and forming positive ions gaining electrons and forming negative ions Correct Answer = A

Ionic Radius Which atom has a radius larger than the radius of its ion? Cl Ca S Se Correct Answer = B

Metals vs. Nonmetals Nonmetals in the solid state are poor conductors of heat and tend to be brittle be malleable have a shiny luster have good electrical conductivity Correct Answer = A

Periodic Table Trends As the atoms in Period 3 of the Periodic Table are considered from left to right, the atoms generally show an increase in radius and an increase in ionization energy an increase in radius and a decrease in ionization energy a decrease in radius and an increase in ionization energy a decrease in radius and a decrease in ionization energy Correct Answer = C

Balancing Equations Given the equation: __FeCl2 + __Na2CO3 → __FeCO3 + __NaCl When the equation is correctly balanced using the smallest whole numbers, the coefficient of NaCl is 6 2 3 4 Correct Answer = B

GFM What is the formula mass of Al2(SO4)3? 123 150. 214 342 Correct Answer = D

Percent by Mass What is the percent by mass of nitrogen in the compound NH4NO3 (formula mass = 80.)? 5.7% 18% 29% 35% Correct Answer = D

Mole to Mole Stoichiometry Given the reaction: CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) How many moles of oxygen are needed for the complete combustion of 3.0 moles of CH4(g)? 6.0 moles 2.0 moles 3.0 moles 4.0 moles Correct Answer = A

Moles to Grams What is the mass of 4.76 moles of Na3PO4 (gram-formula mass = 164 grams/mole)? Answer: 781 g

Grams to Moles The decomposition of sodium azide, NaN3(s), is used to inflate airbags. On impact, the NaN3(s) is ignited by an electrical spark, producing N2(g) and Na(s). The N2(g) inflates the airbag. What is the total number of moles present in a 52.0-gram sample of NaN3(s) (gram formula mass = 65.0 gram/mole)? Answer: 0.800 mol

Percent Water in a Hydrate Lab A hydrate is a compound that includes water molecules within its crystal structure. During an experiment to determine the percent by mass of water in a hydrated crystal, a student found the mass of the hydrated crystal to be 4.10 grams. After heating to constant mass, the mass was 3.70 grams. What is the percent by mass of water in this crystal? 90.% 11% 9.8% 0.40% Correct Answer = C

Types of Reactions Given the balanced equation: 2KClO3 → 2KCl + 3O2 Which type of reaction is represented by this equation? synthesis decomposition single replacement double replacement Correct Answer = B

Bond Breaking vs Bond Making Which statement is true concerning the reaction : N(g) + N(g) → N2(g) + energy? A bond is broken and energy is absorbed. A bond is broken and energy is released. A bond is formed and energy is absorbed. A bond is formed and energy is released. Correct Answer = D

Types of Bonds Which formula represents a compound that is formed primarily by sharing electrons? KCl CaCl2 CrCl3 CCl4 Correct Answer = D

Ionic or Covalent Compound In which compound have electrons been transferred to the oxygen atom? CO2 NO2 N2O Na2O Correct Answer = D

Bond Polarity (Subtract E) The bonds between hydrogen and oxygen in a water molecule are classified as polar covalent nonpolar covalent ionic metallic Correct Answer = A

Molecular Polarity (SNAP) Which type of molecule is CF4? polar, with a symmetrical distribution of charge polar, with an asymmetrical distribution of charge nonpolar, with a symmetrical distribution of charge nonpolar, with an asymmetrical distribution of charge Correct Answer = C

Intermolecular Forces Which attractions are most prevalent between molecules of HF in the liquid phase? van der Waals forces hydrogen bonds molecule-ion attractions ion-ion attractions Correct Answer = B

Heating and Cooling Curves The graph represents the relationship between temperature and time as heat was added uniformly to a substance starting at a solid below its melting point. During the BC portion of the curve, the average kinetic energy of the molecules of the substance increases and the potential energy increases decreases and the potential energy increases remains the same and the potential energy increases remains the same and the potential energy decreases Correct Answer = C

Heat Formulas How many joules of heat energy are released when 50 grams of water are cooled from 70°C to 60°C? 210J 100J 2,100J 1,000J Correct Answer = C

Heat Formulas The heat of fusion of a compound is 333.6 joules per gram. What is the total number of joules of heat that must be absorbed by a 15.0-gram sample to change the compound from solid to liquid at its melting point? 1304J 168J 420J 5004J Correct Answer = D

Combined Gas Law A rigid cylinder with a movable piston contains a 2.0-liter sample of neon gas at STP. What is the volume of this sample when its temperature is increased to 30°C while its pressure is decreased to 90. Kilopascals? 2.5 L 2.0 L 1.6 L 0.22 L Correct Answer = A

Real vs. Ideal Gas The behavior of real gases most closely resembles that of ideal gases under conditions of high temperature and low pressure high temperature and high pressure low temperature and low pressure low temperature and high pressure Correct Answer = A

Solubility Curves According to Reference Table G, which of the following substances is least soluble in 100 grams of H2O(l) at 50°C? KCl NaCl NH4Cl HCl Answer = B

Solubility Curves Based on Reference Table G, which salt solution could contain 42 grams of solute per 100 grams of water at 40°C? a saturated solution of KClO3 a saturated solution of KCl an unsaturated solution of NaCl an unsaturated solution of NH4Cl Correct Answer = D

Solubility Curves A solution contains 35 grams of KNO3 dissolved in 100 grams of water at 40°C. How much more KNO3 would have to be added to make it a saturated solution? 29 g 24 g 12 g 4 g Correct Answer = A

Solubility Factors How does a decrease in temperature from 40°C to 20°C affect the solubility of NH3 (g) and KCl (s)? The solubility of NH3 decreases, and the solubility of KCl decreases. The solubility of NH3 decreases, and the solubility of KCl increases. The solubility of NH3 increases, and the solubility of KCl decreases. The solubility of NH3 increases, and the solubility of KCl increases. Correct Answer = C

Like Dissolves Like Hexane (C6H14) and water do not form a solution. Which statement explains this phenomenon? Hexane is polar and water is nonpolar. Hexane is ionic and water is polar. Hexane is nonpolar and water is polar. Hexane is nonpolar and water is ionic. Correct Answer = C

Molarity (Concnetration) How many liters of a 0.5 M sodium hydroxide solution would contain 2 moles of solute? 1L 2L 3L 4L Correct Answer = D

Colligative Properties What occurs when NaCl(s ) is added to water? The boiling point of the solution increases, and the freezing point of the solution decreases. The boiling point of the solution increases, and the freezing point of the solution increases. The boiling point of the solution decreases, and the freezing point of the solution decreases. The boiling point of the solution decreases, and the freezing point of the solution increases. Correct Answer = A

Neutralization (Titration) What are the products of a reaction between KOH(aq) and HCl(aq)? H2 and KClO H2O and KCl KH and HClO KOH and HCl Correct Answer = B

Titration (Neutralization) In a titration, the endpoint of a neutralization reaction was reached when 37.6 milliliters of an HCl solution was added to 17.3 milliliters of a 0.250 M NaOH solution. What was the molarity of the HCl solution? 0.115 M 0.203 M 0.250 M 0.543 M Correct Answer = A

BONUS What is the correct formula for iron (II) bromide? FeBr2 Fe2Br FeBrO2 Fe2BrO2 Correct Answer = A

BONUS What is the correct formula for ammonium carbonate? NH4(CO3)2 Correct Answer = D